This invention relates to strutless synchronizers for manual transmissions and more particularly to an improved blocking ring strutless synchronizer incorporating resilient torque generating annular springs.
Strutless synchronizers, such as disclosed in the U.S. Pat. No. 3,700,083 issued Oct. 29, 1972 to N. Ashikawa et al. are well known in the synchromesh transmission art. The '083 patent employs a D-section annular spring interposed between a sleeve, slidably mounted on a hub spline of a main shaft, and a blocking ring provided on the conical slidable surface of a speed ratio gear. The annular spring is slidably mounted in a snug manner on the outer surface of three uniformly spaced axially extending lugs integrally formed as the blocking ring. The annular spring interposed between the sleeve and the blocking ring lugs is so arranged that upon movement of the sleeve, the annular spring is first pushed axially by certain of the sleeve internal uniformly spaced splines. This in turn causes the annular spring to axially push the blocking ring. The blocking ring is then seated on the gear cone which, having a relative rotational speed, generates a cone torque to index or clock the blocking ring to the desired blocking position. Once synchronization is complete, the annular spring is then compressed and deflected radially inward by the sleeve as the sleeve passes over the spring. As a result, the sleeve internal splines mesh with a driven gear journaled on the main shaft and thus rotation of the main shaft is transmitted to the driven gear.